B
ELECTRICAL
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
139
Repair and Service Manual
653045
Hydrogen gas formed during bat-
tery charging is explosive.
Avoid any electrical spark or open flame near bat-
tery.
NOTICE: If the temperature of the battery or the
ambient temperature is below 60° F (15.55° C), the
capacity of the battery will be less. It will require
more time to charge.
Voltage on a cold battery increases faster, therefore
decreases the charging rate.
Fully charge a new battery or batteries that have been in
storage before testing or installing in vehicle.
Do not overcharge battery.
STORAGE OF BATTERY
A battery that is removed from service for storage must
be cared for as follows:
For battery removal, see Battery Removal in SAFETY
section. Charge fully. Cover terminals with petroleum jelly
to decrease the risk of oxidation (use commercially avail-
able battery protector when installed in vehicle). Store in a
cool place not below 32° F (0° C) or above 80° F (27° C)
battery should be charged every 30 days using a 2 amp
trickle charger.
DVOM (DIGITAL VOLT OHM METER)
The DVOM shown (Ref. Fig. 8) is representative only.
The actual model may vary depending on availability, and
is available through the Service Parts Department as P/N
27481-G01. For the purpose of this section, the red probe
(+) and black probe (-) are used. Any DVOM may be
used, however the controls, displays, accuracy and fea-
tures may vary depending on the make and model.
Always follow the meter manufacturer’s recommenda-
tions and instructions for the use and care of the meter.
Fig. 8 DVOM
FAULT TESTING
Knowledge of use of wiring diagrams and a Digital Volt
Ohm Meter (DVOM) is necessary to effectively determine
fault within the circuits that include the horn, lighting,
brake/turn signals and gages.
The wiring diagram shows the path followed by a voltage
or signal from its origination point to its destination. Each
wire is indicated by color and is divided into the main har-
ness and the dash harness.
Knowledge of simple logic fault testing will decrease the
number of steps required to isolate the problem.
Example 1:
If the vehicle does not start and none of the
lights function (or burn dimly), test the battery before try-
ing to determine fault within the lighting circuit.
Example 2:
If a problem occurs in the lighting circuit that
causes only one of the headlights to fail, it is not neces-
sary to check the battery wiring or the fuse since voltage
is present. Check the headlight that is not operating. If
power is found at the connector and the ground wiring is
satisfactory, it is a burned out bulb or a poor contact
between the connectors and the headlight.
If power is not present but the other headlight functions, a
wiring problem is indicated between the two headlights.
In some cases where battery voltage is expected, the
easiest way to test the circuit is to set the DVOM to DC
volts and put the negative (-) probe on the negative bat-
tery terminal. Move the positive (+) probe to each wire ter-
minal starting at the battery and moving out to the device
that is not working. Check both sides of all switches and
Cover
Data-h
Switch
Range
Switch
Transistor
Socket
+ Test Lead
- Test Lead
Test
Receptacles
Function
Selector
Switch
Continuity
Test Diode
Test, Ac/dc
Current
Toggle
Switch
Digital
Display
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